My neuro-otologist just prescribed SERC (betahistine) to me for inner ear/vestibular disorders and I haven't tried it yet. It's only available in Canada but a US doctor can prescribe it.

My inner ear disorder came before my concussion, but the things that helped me in the past to minimize "attacks" of ear fullness, imbalance, brain fog, and in my case hearing loss, were very similar to concussion recovery: drinking lots of water, taking vitamins, getting enough sleep, avoiding stress and exposure to chemicals, low sodium diet, avoiding MSG, sodium nitrates, caffeine, and especially alcohol.

Sorry you're experiencing these things, best wishes.